Reliability of Obstacle-Crossing Parameters during Overground Walking in Young Adults.

We aimed to evaluate the intra-session relative and absolute reliability of obstacle-crossing parameters during overground walking in young adults, and to determine the number of trials required to ensure reliable assessment. We analysed data from 43 young male adults who were instructed to walk at a self-selected velocity on a pathway and to step over an obstacle (height = 15 cm; width = 80 cm, thickness = 2 cm) three times. Spatial-temporal gait parameters of the approaching and crossing phases (i.e., before and after the obstacle) and obstacle clearance parameters (i.e., vertical and horizontal distance between the foot and the obstacle during crossing) were computed using a three-dimensional motion analysis system. Intraclass correlation coefficients were used to compute the relative reliability, while standard error of measurement and minimal detectable change were used to assess the absolute reliability for all possible combinations between trials. Results showed that most spatial-temporal gait parameters and obstacle clearance parameters are reliable using the average of three trials. However, the mean of the second and third trials ensures the best relative and absolute reliabilities of most obstacle-crossing parameters. Further works are needed to generalize these results in more realistic conditions and in other populations.

Reduced trunk movement control during motor dual-tasking in older adults.

Older adults have a decreased trunk movement control which is linked to their higher fall risk. While motor/cognitive dual-tasking deteriorates balance and walking in older adults, there is limited understanding on how trunk kinematics and kinetics are affected by dual-tasking in scenarios where falls can occur. Therefore, the purpose of the study was to determine the impacts of a challenging motor dual-task, specifically obstacle avoidance during walking, on trunk and lower-body kinematics and kinetics of older adults compared to young adults. The study captured three-dimensional kinematic and kinetic data from 12 young adults and 10 older adults as they walked on a treadmill and stepped over an obstacle with both legs. The study analyzed trunk, hip, knee, and ankle angles and torques. Trunk torque was further broken down to trunk muscle torque, gravitational torque, and inertia torque. A linear mixed effects model was used to investigate the difference in each variable between the two groups. Older adults exhibited significantly increased trunk flexion angle and trunk extension muscle torque compared to young adults, with the trunk being the only segment/joint showing differences in both kinematics and kinetics. Trunk torque breakdown analysis revealed that larger trunk flexion led to a larger gravitational torque, which contributed to an increased compensatory trunk muscle torque. Moreover, older adults' less controlled trunk flexion during weight shifting from trail leg to the lead leg, necessitated a compensatory trunk deceleration during trail leg obstacle avoidance which was achieved by generating additional increase in trunk muscle torque. The study demonstrated that motor dual-tasking has the most negative effects on trunk control in older adults compared to young adults. This exposes older adults to a higher fall risk. Therefore, future work should focus on supporting trunk control during daily multi-tasking conditions where falls can occur.

How do features of dynamic postural stability change with age during quiet standing, gait, and obstacle crossing?

Previous research has reported mixed findings regarding age-related changes in dynamic postural stability, quantified by margin of stability (MOS), during gait. However, age-related changes in MOS may be better elicited by tasks imposing greater challenges to the postural control system. Older adults' MOS during obstacle crossing, a destabilizing task, has previously been characterized, although studies comparing MOS during this task between younger and older adults remain sparse. This study investigated age-related changes in dynamic postural stability during quiet standing, gait, and obstacle crossing. Participants aged 20-30 (n = 20), 60-69 (n = 18), 70-79 (n = 15), and 80+ (n = 7; not analyzed statistically) years old performed these tasks while whole-body motion was tracked using motion capture. MOS in each direction was estimated throughout each trial, and integrals, transient ranges, and trial minima were extracted (as applicable). MOS time series were also ensemble averaged across age groups. No age-related differences were identified for quiet standing or gait. However, obstacle crossing metrics revealed greater stability (i.e., more positive MOS) and less instability (i.e., less negative MOS) in older adults, and reduced ranges during transients. These findings potentially arise from shorter step lengths, which may be the result of age-related physical declines; or may reflect a cautious strategy in older adults, which maximizes postural stability in the direction with the greatest consequences for foot-obstacle contact, as it changes throughout the task. This study supports the use of tasks imposing physical challenges and/or voluntary perturbations to study age-related changes in dynamic postural stability. Findings also contribute to our theoretical understanding of the time course of dynamic postural stability during functional tasks in relation to periods of transition in the base of support, and task-specific strategies adopted for obstacle crossing by older adults to maintain dynamic postural stability and mitigate fall risk.

Effects of a 12-week online Tai Chi intervention on gait and postural stability in individuals with Parkinson's disease.

Parkinson's disease (PD) affects gait and postural stability. Tai Chi (TC) is recommended for PD for management of the condition, however biomechanical understanding to its effects on gait and postural stability is limited. This study aimed to examine the effects of an online 12-week biomechanical-based TC intervention on gait and posture in people with PD. Fifteen individuals in early-stage PD were recruited (Hoehn & Yahr stages 1-2). The TC intervention program was 60 â€‹min session, three times weekly for 12 weeks. The pre- and post-intervention test in obstacle crossing, timed-up-and-go (TUG) test, and single leg standing (SLS) with eyes open (EO) and closed (EC) were conducted. Gait speed, crossing stride length, clearance height of the heel and toe, anterior-posterior (AP) and medial-lateral (ML) displacement and velocity of the center of mass (COM) and separation of the COM-center of pressure (COP) were analyzed. The participants significantly improved their pre-vs. post-TC intervention performance on TUG test (p â€‹= â€‹0.002). During obstacle crossing, the participants significantly increased crossing stride length of the trailing foot, increased AP COM displacement and decreased ML COM-COP separation (p â€‹< â€‹0.05); the maximal dorsiflexion angle of the leading limb significantly increased and maximal plantarflexion angle of the trailing limb significantly decreased (p â€‹< â€‹0.05). A 12-week biomechanical-based online TC training was effective towards improvement of gait and postural stability among people in the early-stage of PD. The TC program and online training could be applied for management of PD.

Relation between the kinematic synergy controlling swing foot and visual exploration during obstacle crossing.

To step over obstacles of varying heights, two distinct ongoing streams of activities-visual exploration of the environment and gait adjustment- were required to occur concurrently without interfering each other. Yet, it remains unclear whether and how the manner of embodied behavior of visual exploration is related to the synergistic control of foot trajectory to negotiate with the irregular terrain. Thus, we aimed to explore that how the synergistic control of the vertical trajectory of the swing foot (i.e., obstacle clearance) crossing an obstacle is related to the manner of visual exploration of the environment during approach. Twenty healthy young adults crossed an obstacle (depth: 1 cm, width: 60 cm, height: 8 cm) during their comfortable-speed walking. The visual exploration was evaluated as the amount of time spent in fixating the vicinity of the obstacle on the floor during the period from two to four steps prior to crossing the obstacle, and the strengths of kinematic synergy to control obstacle clearance were estimated using the uncontrolled manifold approach. We found that the participants with relatively weak synergy spent more time fixating at the vicinity of the obstacle from two to four steps prior to crossing the obstacle, and those participants exhibited greater amount of head flexion movement compared to those with stronger kinematic synergy. Taking advantage of this complex relationship between exploratory activities (e.g. looking movement) and performative activities (e.g. adjustment of ground clearance) would be crucial to adapt walking in a complex environment.

A Systematic Review of the Influence of Overweight and Obesity across the Lifespan on Obstacle Crossing during Walking.

This study aimed to systematically review and summarize the available data regarding the influence of overweight and obesity across the lifespan on obstacle crossing during walking. Four databases were systematically searched with no limitation on publication date following the Cochrane Handbook for Systematic Reviews and PRISMA guidelines. Only full-text English-language articles published in a peer-reviewed journal were eligible. They had to compare obstacle crossing during walking by overweight or obese individuals with individuals of normal body weight. Five studies were considered eligible. All the studies assessed kinematics; only one assessed kinetics, but none investigated muscle activity or obstacle contact. Compared to normal individuals crossing obstacles, overweight or obese individuals exhibited lower velocity, shorter step length, lower cadence, and less time spent in single-limb support. They also exhibited increased step width, more time spent in double support, and greater trailing leg ground force reaction and centre of mass acceleration. Overall, the small number of included studies did not allow us to draw any conclusions. However, being overweight or obese seems to have a potentially negative influence on the kinematics of gait parameters due to a tendency to trip, fall, and suffer severe fall-related injuries when negotiating obstacles on foot in real-life environments.

Influence of obstructions on obstacle-crossing motion during walking.

[Purpose] The purpose of this study was to clarify whether the presence of obstructions changes the crossing motion during walking based on the visual perception of obstacles. [Participants and Methods] We included 25 healthy university students as the participants in this study. They were asked to step over obstacles while walking under two conditions i.e., with obstruction and without obstruction. We analyzed the distance between the foot and obstacle (clearance), trajectory of foot pressure movement and distribution as measured by a foot pressure distribution measurement system, and stance phase time. [Results] No significant differences were found between the two conditions for either clearance or foot pressure distribution. In other words, no difference in crossing motion was observed after visual recognition of the obstacle, both in the presence or absence of the obstruction. [Conclusion] The results suggest that no differences exist in the accuracy of recognizing visual information about an obstacle through different mechanisms of selective visual attention.

Enhancement of awareness through feedback does not lead to interlimb transfer of obstacle crossing in virtual reality.

Locomotor skill transfer is an essential feature of motor adaptation and represents the generalization of learned skills. We previously showed that gait adaptation after crossing virtual obstacles did not transfer to the untrained limb and suggested it may be due to missing feedback of performance. This study investigated whether providing feedback and an explicit goal during training would lead to transfer of adaptive skills to the untrained limb. Thirteen young adults crossed 50 virtual obstacles with one (trained) leg. Subsequently, they performed 50 trials with their other (transfer) leg upon notice about the side change. Visual feedback about crossing performance (toe clearance) was provided using a color scale. In addition, joint angles of the ankle, knee, and hip were calculated for the crossing legs. Toe clearance decreased with repeated obstacle crossing from 7.8 ± 2.7 cm to 4.6 ± 1.7 cm for the trained leg and from 6.8 ± 3.0 cm to 4.4 ± 2.0 cm (p < 0.05) for the transfer leg with similar adaptation rates between limbs. Toe clearance was significantly higher for the first trials of the transfer leg compared to the last trials of the training leg (p < 0.05). Furthermore, statistical parametric mapping revealed similar joint kinematics for trained and transfer legs in the initial training trials but differed in knee and hip joints when comparing the last trials of the trained leg with the first trials of the transfer leg. We concluded that locomotor skills acquired during a virtual obstacle crossing task are limb-specific and that enhanced awareness does not seem to improve interlimb transfer.

Effects of simulated trunk flexion contracture on the margin of stability during obstacle crossing in elderly individuals.

BACKGROUND: Trunk flexion contracture is an abnormal posture in elderly individuals with lumbar kyphosis. It is unclear whether this posture affects locomotor stability (margin of stability [MoS]) during obstacle crossing, which is a common trigger for falls in elderly people. RESEARCH QUESTION: Does trunk flexion contracture negatively affect MoS during obstacle crossing in elderly people? METHODS: Ten healthy elderly individuals performed five trials of obstacle crossing using a comfortable speed under two experimental conditions, namely, with (FLEX) or without (NORMAL) a hard lumbar brace to simulate trunk flexion contracture. The obstacle-crossing motion was captured using an optical motion analysis system in order to calculate the MoS in the anteroposterior direction. The MoS at initial contact (IC) and that when the swing foot was above the obstacle (Obs) was compared between FLEX and NORMAL. A greater MoS suggests greater risk of a forward fall. The trunk and lower limb joint angles were measured at Obs. RESULTS: FLEX significantly increased the MoS at IC, whereas the MoS at Obs did not differ between the two conditions. FLEX demonstrated a crouch posture characterized by an increased flexion angle of stance-side hip and knee joints at the Obs instant. SIGNIFICANCE: Forward fall chance might be increased at IC in obstacle crossing with trunk flexion contracture. Meanwhile, the MoS at Obs might be controlled by increasing the crouch posture to offset a forward shift in the CoM position due to the trunk flexion. Because the risk of a stumble on an obstacle and of forward falls should be higher at Obs than at IC, the crouch posture seems to be an effective adaptation that enables elderly people with trunk flexion contracture to safely cross obstacles.

Lower-limbs' muscle coordination mechanism of healthy preschoolers while walking across obstacles.

RESEARCH BACKGROUND: The obstacle-crossing task is a complex gait task, it requires an advance predict of the obstacle for posture adjustment and accurate control of bilateral legs to ensure crossing the obstacles successfully. By monitoring the activated intensity and duration of muscles in this process, preschoolers' motor ability could be assessed objectively and quantitatively, as well as disclose their potential pathogenesis quality eventually. SCIENTIFIC QUESTION: what are the patterns and characteristics of lower limb muscles when they are facing the obstacle-crossing walking (OW) tasks, and how they coordinate their individual muscle or muscle groups of lower-limbs muscles while walking across obstacles? Thereby, the purpose of this study was first to portray the patterns and characteristics of lower limb muscles of healthy preschoolers while OW motion and second to assess the muscles' coordination mechanism. METHOD: 35 healthy preschoolers and 35 healthy adults' lower limbs' surface electromyography (sEMG) were collected while left and right OW and four muscle groups (Tibialis Anterior, Lateral Gastrocnemius, Rectus Femoris, and Biceps Femoris) were recorded. sEMG variables such as Muscle Activation Time, Total Duration of Activity Time, Average Muscle Activation Rate, and Average Rate of Change were calculated. The paired sample-t-test was used to explore the differences of sEMG variables between preschoolers and adults when obstacle-crossing. RESULTS: Preschoolers would adjust the gait by changing the activation time and activation rate to fulfill the obstacle crossing tasks, but they also showed variations by contrasting to adults. Further, synergy between muscles in leg and thigh were also found. CONCLUSION: Although preschoolers performed well enough to finish the OW tasks, ability gaps were still apparent when compared to adults. Hence, with the help of a deeply recognizable muscle coordination mechanism in OW, motor dysfunction in the lower limbs of preschool children can be effectively identified.

Between a Walk and a Hard Place: How Stepping Patterns Change While Navigating Environmental Obstacles.

Maintaining a consistent relationship between each footfall and the body's motion is a key mechanism to maintain balance while walking. However, environmental features, for example, puddles/obstacles, impose additional constraints on foot placement. This study investigated how healthy young individuals alter foot placements to simultaneously manage body-centric and environmental constraints during an obstacle-crossing task. Consistent step length promotes balance for all steps, whereas accurate foot placement around the obstacle is essential to avoid a trip. While crossing an obstacle, any error in positioning one foot relative to the obstacle can be compensated by selecting the placement of the subsequent step. However, compensation will necessarily alter step length from its average value. The interstep covariance index computed from two consecutive foot placements was used to quantify this tradeoff between body-centric and environmental constraints for six consecutive steps while approaching, crossing, and resuming unobstructed gait after crossing the obstacle. The index declined only when either one or both feet were adjacent to the obstacle. The decline was driven in part by a tendency toward higher step length variability. Thus, changes in the stepping patterns to address the environmental constraint occurred at the cost of the body-centric constraint. However, the step length never ceased to be controlled; the interstep covariance index was positive for all steps. Overall, participants adapted foot placement control to account for the larger threat to balance. The environmental constraint was prioritized only when a potential trip posed greater threat to balance compared with the threat posed by variable step length.

Design and dynamic analysis of jumping wheel-legged robot in complex terrain environment.

Wheel-legged robots have fast and stable motion characteristics on flat roads, but there are the problems of poor balance ability and low movement level in special terrains such as rough roads. In this paper, a new type of wheel-legged robot with parallel four-bar mechanism is proposed, and the linear quadratic regulator (LQR) controller and fuzzy proportion differentiation (PD) jumping controller are designed and developed to achieve stable motion so that the robot has the ability to jump over obstacles and adapt to rough terrain. The amount of energy released by the parallel four-bar linkage mechanism changes with the change of the link angle, and the height of the jump trajectory changes accordingly, which improves the robot's ability to overcome obstacles facing vertical obstacles. Simulations and real scene tests are performed in different terrain environments to verify obstacle crossing capabilities. The simulation results show that, in the pothole terrain, the maximum height error of the two hip joint motors is 2 mm for the obstacle surmounting method of the adaptive retractable wheel-legs; in the process of single leg obstacle surmounting, the maximum height error of the hip joint motors is only 6.6 mm. The comparison of simulation data and real scene experimental results shows that the robot has better robustness in moving under complex terrains.

Kinematic strategies for obstacle-crossing in older adults with mild cognitive impairment.

Introduction: Mild cognitive impairment (MCI) is considered a transitional stage between soundness of mind and dementia, often involving problems with memory, which may lead to abnormal postural control and altered end-point control when dealing with neuromechanical challenges during obstacle-crossing. The study aimed to identify the end-point control and angular kinematics of the pelvis-leg apparatus while crossing obstacles for both leading and trailing limbs. Methods: 12 patients with MCI (age: 66.7 ± 4.2 y/o; height: 161.3 ± 7.3 cm; mass: 62.0 ± 13.6 kg) and 12 healthy adults (age: 67.7 ± 2.9 y/o; height: 159.3 ± 6.1 cm; mass: 61.2 ± 12.0 kg) each walked and crossed obstacles of three different heights (10, 20, and 30% of leg length). Angular motions of the pelvis and lower limbs and toe-obstacle clearances during leading- and trailing-limb crossings were calculated. Two-way analyses of variance were used to study between-subject (group) and within-subject (obstacle height) effects on the variables. Whenever a height effect was found, a polynomial test was used to determine the trend. A significance level of α = 0.05 was set for all tests. Results: Patients with MCI significantly increased pelvic anterior tilt, hip abduction, and knee adduction in the swing limb during leading-limb crossing when compared to controls (p < 0.05). During trailing-limb crossing, the MCI group showed significantly decreased pelvic posterior tilt, as well as ankle dorsiflexion in the trailing swing limb (p < 0.05). Conclusion: Patients with MCI adopt altered kinematic strategies for successful obstacle-crossing. The patients were able to maintain normal leading and trailing toe-obstacle clearances for all tested obstacle heights with a specific kinematic strategy, namely increased pelvic anterior tilt, swing hip abduction, and knee adduction during leading-limb crossing, and decreased pelvic posterior tilt and swing ankle dorsiflexion during trailing-limb crossing. The current results suggest that regular monitoring of obstacle-crossing kinematics for reduced toe-obstacle clearance or any signs of changes in crossing strategy may be helpful for early detection of compromised obstacle-crossing ability in patients with single-domain amnestic MCI. Further studies using a motor/cognitive dual-task approach on the kinematic strategies adopted by multiple-domain MCI will be needed for a complete picture of the functional adaptations in such a patient group.

Synergistic multi-joint kinematic strategies to reduce tripping risks during obstacle-crossing in older long-term Tai-Chi Chuan practitioners.

Introduction: Losing balance or tripping over obstacles is considered one of the most common causes of falls in the elderly. Tai-Chi Chuan (TCC) has been shown to improve muscle strength, inter-joint coordination and balance control in the elderly. This study aimed to determine whether older long-term TCC practitioners would show multi-joint kinematic strategies that would reduce the risk of tripping during obstacle-crossing compared to peers without TCC experience. Methods: Three-dimensional motions of the pelvis and lower extremities were measured using a motion capture system in fifteen older long-term TCC practitioners (TCC group) and 15 healthy controls without TCC experience during walking and crossing obstacles of three different heights. Crossing angles of the pelvis and lower limbs and toe-obstacle clearances were obtained and analyzed using two-way analyses of variance to study the between-subject (group) and within-subject (height) effects. A multi-link system approach was used to reveal the relationship between joint angular changes and toe-obstacle clearances. Results: Compared to the controls, the TCC group showed increased leading and trailing toe-obstacle clearances (p < 0.05) with increased pelvic hiking and hip flexion but decreased hip adduction on the swing side and decreased knee flexion on the stance side during leading-limb crossing (p < 0.05), and increased pelvic hiking and anterior tilt but decreased hip adduction on the swing side, and decreased knee flexion on the stance side during trailing limb crossing (p < 0.05). All significant joint angular changes contributed to the increases in the toe-obstacle clearances. Conclusion: The current study identified the kinematic changes of the pelvis and the lower limb joints and revealed a specific synergistic multi-joint kinematic strategy to reduce tripping risks during obstacle-crossing in older long-term TCC practitioners as compared to non-TCC controls. The observed multi-joint kinematic strategies and the associated increases in toe-obstacle clearances appeared to be related to the training characteristics of TCC movements. Long-term TCC practice may be helpful for older people in reducing the risk of tripping and the subsequent loss of balance.

The effects of experimentally-induced fatigue on gait parameters during obstacle crossing: A systematic review.

Striking an obstacle while walking can be dangerous, reflecting the higher risks of losing one's balance, tripping and falling. Particular situations during which internal resources are limited, such as in a fatigued state, may impair performance when crossing obstacles, enhancing the risks of falls or accidents. Our goal was thus to review the effects of experimentally-induced fatigue (EIF) on gait parameters during obstacle crossing by healthy individuals. We systematically searched PubMed and Web of Science databases using 'fatigue', 'obstacle crossing' and their equivalent terms to extract data from studies investigating this domain. Nine studies were found. First, EIF-related effects on kinetics, EMG and obstacle contacts have been poorly studied. Second, consistent and inconsistent results were found in the kinematic outcomes after EIF. Consistent results included reductions in stride duration and increased step width. Inconsistent results included gait velocity (no-effect vs increased), leading and trailing-foot vertical clearance (reduced vs increased) and horizontal distance from foot to the obstacle before obstacle avoidance (no-effect vs increased). These findings should be interpreted cautiously, however, due to the heterogeneity of the obstacle crossing and EIF protocols.

Modeling, Simulation and Implementation of All Terrain Adaptive Five DOF Robot.

The ability of an off-road robot to traverse obstacles determines whether the robot can complete complex environmental tasks. In order to improve the off-road ability of off-road robots, this paper proposes a new design idea, in which four hub motors are the power system of the robot, the steering system of the robot is composed of a steering machine and a stepping motor, and a five degree of freedom robot model is established. The body structure is designed according to the characteristics of arthropods. The body structure is divided into three modules, and the connecting rod is used as the joint system of the robot to connect the three parts. The body can deform when facing complex obstacles, so as to adapt to different terrains. Then the body structure is simplified, and a mathematical model is established to describe the mathematical relationship between body joint changes. In order to verify the ability of the adaptive all-terrain cross-country robot to traverse obstacles, the load-bearing experiment and obstacle-crossing simulation experiment were carried out through Adams software, and the continuous traversing performance at low obstacles and the ability to break through high obstacles were tested, respectively. The experimental results prove that the designed adaptive all-terrain off-road robot is feasible, has good carrying capacity, and has good passability in the face of low obstacles and high obstacles. Using Ansys software to perform finite element analysis on the wheel connection, the experimental results show that the strength meets the material strength requirements. Finally, a real vehicle test is carried out to verify the correctness of the simulation results.

Age-Related Changes in Accuracy and Speed of Lateral Crossing Motion: Focus on Stepping from Leaning Position.

Fall incidents are increasing every year and prevention is necessary. Preventing falls can increase the quality of life of the elderly and decrease medical costs. Stumbling and tripping are the main causes of falls and falls in the lateral direction, causing the hip fracture. This study aimed to analyze the accuracy and speed of lateral obstacle crossing in the elderly, especially from leaning posture. Twenty healthy older adults (6 men and 14 women, aged 71.7 ± 1.5 years) and 20 healthy young adults (5 men and 15 women, aged 21.4 ± 1.2 years) participated in this study. We set four conditions (normal, fast, leaning, and leaning fast), and participants crossed the obstacle laterally ten times under each condition. The crossing motion was captured using a three-dimensional analysis system. The trajectory of the foot, landed position, step time, center of gravity of the body, and moment of the lower extremity during the swing phase were calculated and compared between older and younger adults. In the leaning condition, the step time and knee moment of the elderly were significantly longer and larger than those of young adults. From the results of the trajectory of the foot and landed position in the leaning condition, motion inconsistency of the foot was found in the elderly. We believe that it is difficult for the elderly to perform the intended crossing motion and swing quickly because of aging. This inconsistency in motion is a serious cause of falls in the elderly.

Ground Reaction Forces and Center of Pressure within the Paws When Stepping over Obstacles in Dogs.

Walking over obstacles is a widely used physiotherapy exercise in dogs. Current research is limited to the effect of this exercise in kinematics and muscle activation in dogs. The present study assessed the influence of walking over obstacles on the ground reaction forces (GRFs) and center of pressure (COP) in dogs. Data of dogs walking over one and two obstacles over a pressure platform were retrospectively analyzed and compared to normal walking. Walking over one obstacle did not affect the GRFs and COP of the forelimbs; however, significant changes were observed for the hindlimbs, especially the leading hindlimb. Walking over two obstacles caused significant changes to only one value at the forelimbs, whereas multiple significant changes in the GRFs and COP values were observed at the hindlimbs. Walking over obstacles seems to be challenging even for healthy adult dogs. Further studies are needed to investigate how different heights of obstacles and distances between them can further challenge the animals. The combination of kinetics and kinematics during walking over obstacles may be used in future as a diagnostic tool in geriatric and neurological patients in order to assess their proprioception awareness or to assess the improvement after an intervention, e.g., physiotherapy treatment.

The Effects of Overweight and Obesity on Obstacle Crossing During Walking: Protocol for a Systematic Review.

BACKGROUND: Overweight and obesity are significant global health concerns that involve deficits in gait and balance that affect daily activities. Although much is reported about the effect of overweight and obesity on gait during unobstructed walking, not much is known about how overweight and obesity could impact gait under more challenging conditions, such as environments with obstacles. OBJECTIVE: The aim of this study is to systematically review and synthesize the available data regarding the effects of overweight and obesity on obstacle crossing during walking. METHODS: This review will follow the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines. PubMed, Web of Science, Scopus, and SPORTDiscus will be systematically searched with no limitations on publication date. Only full-text English-language articles published in a peer-reviewed journal will be included. Included articles must have compared obstacle crossing during walking in individuals with overweight or obesity to individuals of normal body weight. A total of 2 independent reviewers will select the articles and extract the following 4 sets of data: (1) study characteristics, (2) sample description, (3) obstacle crossing task protocol, and (4) main results obtained. If a considerable number of homogeneous papers are included, a meta-analysis will be conducted. A preliminary search was conducted in November 2021. RESULTS: The results will include the article selection flowchart as well as tables and figures synthesizing the extracted data on the effects of overweight and obesity on obstacle crossing during walking. The preliminary search identified 73 original records, of which 5 articles met the inclusion criteria. CONCLUSIONS: This review will present researchers and clinicians with an overview of published studies that have compared the performance of obstacle crossing for individuals with overweight and obesity to those of normal body weight. Gaining insight into the control strategies adopted by individuals with overweight and obesity is critical for safe and successful obstacle crossing in this population. We therefore believe that our findings could be useful for identifying people at risk of falls and developing and implementing fall prevention programs for individuals with overweight and obesity. TRIAL REGISTRATION: PROSPERO CRD42021269949; https://tinyurl.com/3yrwccu4. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/36234.

Different Effects of 12-Week Speed or Accuracy Training on Obstacle-Crossing Foot Motion in Healthy Elderly.

Preventing falls is important in the elderly. One reason for falling is tripping or stumbling; hence, it is important to improve the crossing motion. This study aimed to compare speed- and accuracy-oriented crossing training and establish a useful training method. To investigate the effects of crossing motion training, we conducted a randomized controlled trial. Twenty healthy elderly individuals (aged 71.7 ± 1.5 years) were randomly assigned to two groups: speed training and accuracy training groups. They practiced initiating their crossing motion faster or more accurately for 12 weeks. Using a three-dimensional motion analysis system, the data on the crossing motion was captured before and after the training period. We set four conditions (normal speed, fast, leaning stance, and leaning stance and fast) and two directions (anterior and lateral) to analyze the crossing motion. The crossing motion of the speed training group became significantly faster compared to baseline (p < 0.05); however, the accuracy of the crossing motion of the accuracy training group was not statistically significant. Speed training in this study had clear effects on crossing motion. It is surprising that crossing motion training from a normal upright stance can also improve swing speed from the leaning stance. We believe that this training is easy and useful in the elderly population.